Refrigerating apparatus



Sept 15, 1931- `s. c. cARNEY l 1,823,725

BEFRIGERATI NG APPARATUS Sept. 15, 1931. s. c. CARNI-:Y

REFRIGERATING APPARATUS Filed Dec. '7. 1925 l L. IIIIIHIIII 2Sheets-Sheet 2 rafeniecl sept. 1.5,` 1931 UNITED STATES PATENT OFFICESAMUEL l(Il. CARNEY, OF TULSA, OKLAHOMA, ASSIGNOR TO SHELL PETROLEUMCORPO- RATION, A CORPORATION F VIRGINIA REFRIGERATING APPARATUSApplication led December 7, 1925. Serial No. 73,851.

This invention relates to improvements in refrigerating apparatus andconsists in the novel construction hereinafter' disclosed.

An object ofthe present invention is to provide an apparatus whereby arefrigerant is kept in constant Contact, largely in liquid form, withthe inner surface of a rotating drum, said drum being mounted within achamber in which the pressure may be re.

duced below -atmospheric and to the outer periphery of which a supply ofliquid to be frozen is conducted together with means for removing theliquidv frozen on the periphery of the drum, whereby itmay be packedinto cakes for commercial purposes.

Generally stated, the invention consists of the novel construction,arrangement and combination of parts hereinafter described andtheparticular advantageous features of the structure will be readilyrecognized from the detailed disclosure thereof,taken in connectidn withthe accompanying drawings in i which Fig/1 is a vertical sectionthroughy the apparatus;

Fig. 2 is across section; and

Fig. 3 is a detail viewin vertical section :of the mold for compactingand removing in cake form the frozen liquid producedby the apparatus.

I-Ieretofore, in practice, in the manufac ture of ice commercially therehas been employed two general systems, namely, the can system and theplate. system. In both of these, the heat from the liquid being frozenmust be transmitted at a relatively low temcomes covered with athickcoating of the .frozen liquid, after which the heat is required to passfrom the liquid to be frozen through a considerable thickness of thefrozen mass, thus greatly reducing the effectivenessof the system as awhole.

Furthermore in the existing systems, the metallic surfaceof the pipecoil or the chamber in which the refrigerating liquid is beingevaporated is, to a considerable extent, in contact with the vapor ofthe refrigerating liquid rather than with the liquid itself. Especiallyis Vthis true in a long pipe coil, because the vapor of the liquid firstevaporated must pass through the remaining length of the coil leading tothe compressor or absorber. This results in a low coefficient of heattransmission, because a considerable part o f the coil surface, namely,that part which is in contact only with the vapor on one side and withthe brine solution or wap ter on the other side, has an extremely lowrate of heat transfer. VvFurthermore the brine solution or water incontact with' the evaporating coils or chamber causes corrosion of.

the metal of the'refrigerant container, thereby further reducing therate of heat transfer. The apparatus of the present invention 'overcomesthe difficulties inherent in the present systems by freezing'theliquidsby means of heat transfer through a relatively thin metallic surface ofhigh heat conductivity and removing the frozen bodies in a relativelysmall mass, thereby obtaining a high rate of heat transfer andahighefliciency from the refrigerant. f

In the embodiment of the invention shown in the drawings, the foregoingresults are accomplished by an apparatus comprising a `housing whichincludes four segmental sections 1, 2, 3 and 4 respectively, havinmatching flanges 5 which are bolted together to form a chamber havingsubstantially the` cross sectional area illustrated (Fig. L2). Thehousing is supported by legs 6 for conveniently mounting it foroperation. The

ends of the housing are closed by end plates 7 and 8 which are bolteddirectly to flanges 9 formed at the ends of the segments, form.

ling the body of the housing.- The entire 'opposite' ends.

housing is preferably exteriorly insulated by insulating material 10covering the exposed surfaces thereof.

The castings, forming the housing are joined together so as to formtightseals permitting a partial vacuum to be maintained therein. Whilethe maintenance of a vacuum in the housing is not essential in allcases, it is generally preferable however forthe purpose of removing airor other dissolved gases from the liquids being fro zen. Furthermore,the vacuum acts as an insulating acket preventing undue heat transferfrom the exterior of the housing, and thereby -maintaining the loweredtemperature within the housing during the freezing operation.

The housing is therefore provided with a top opening 11 into which a'pipe from a vacuum pump may be connected for the purpose of exhaustingto the vvrequired degree the` air from the housing and thereby to main-The 'housing is also preferably equipped with sight openings 12conveniently arranged so that the operation of the device may beobserved.

v.These sight openings are closed by transparent sight glasses 13, itbeing understood that it ispreferable to construct the sight openings sothat there will b'e-heat insulation sufficient to avoid the rise oftemperature above the desired internal temperature in the housing ofapproximately thirty-two vdegrees-when ice is manufactured by theapparatus. If the apparatus is usedfor freez- -ing other liquids,necessarily a corresponding internal temperature for freezing suchliquid will be maintained.

VA revolvingdrum is mounted within the housing,` said drum comprising acylindrical wall 14preferably made of a relatively thin metal having ahigh heat conductivity. The endsof the drum are closed by 'end 'plates15 which extend beyond the end of and are connected with the member 14at The walls -15 are insulated by insulating material 16'. The drum issupported for rotation in the housing by hollow shafts. 17 and 18, saidshafts leing directly connected to the respective end` plates 15 at thecenter thereof. .Said shafts 17 and 18 communicate directly with theinterior of the drum. They extend` through the end plates 7 "and 8,rstuffing boxes 19 being provided to seal the openings through which saidshafts extend. The shaft 17 is journaled in a bearing 20 supported by abracket 21, said shaft carrying a pulley 22 by means of which the shaftand therefore the drumv may be rotated from any suitable source ofpower.l

Thel outer end of the shaft 17 is connected into a` chamber 23, theopening through which the conneetionnwith'the chamber 23. is made issealed by a stutling box 24. The' chamber 23 is supported bya bracket 25in parallel alinement with the bracket 21 and has an outlet opening 26into whichv a pipe zle 31, the opening Aof which is slightly below thescraping knife presently to be described.

A series of troughs are arranged around the interior Vwall of the drum,said troughs being composed of inwardly curved walls 32 connected -attheir outer end directly With the wall 14 ,and running longitudinallytherewith. The Walls 32 have upturned flanges 33 at theirinner ends,said flanges being slightly spaced apart, thus forming a plurality oftroughs with longitudinal openn ings 4in the center tlereof runningparallel with the axis of the drum. A series of pipes 34 extend `fromone trough to another, the connected troughs beingl approximatelysixty'degrees apart. By reference to Fig. 2 of the drawings, it will benotedthat the pipes V34 connect alternate ones of `the troughs-which isa suitable arrangement for the number shown in the drawings.

From the description of the refrigerant supply pipe and the arrangementof the troughs with their cross `connecting it will be understood thatthe original refrigerant supply discharged from the nozzle 31 issupplied to the troughs successively as they pass a point in theirrotation slightly below the position of the scraping knife abovereferred to. Intercommunication between the troughs is foratingftheWalls 32 along a line of their juncture with the wall surfaces 14 andin- Pipes,

provi/ded for by perf dicated on the drawings by the numeral 35; l

poured into the troughs on the descending` part of the revolution andthere is also poured into the descending troughs through the' crossconnecting pipes 34 refrigerant which has not leaked out through theperforatlons 35 on the ascending part of the is picked upby the troughsas they successively pass the lowest point in their revolution fordistribution to the ascending part of the drum surface by leakage throuh perforations 35 and for transferthroug pipes 34- from the troughscompleting the ascending part of the revolution to those beginning thedescent.

t Extending longitudinally of the housing ,are two supply pipes 36 and37, the supply pipe 36 being arranged near the top of the housing and ina plane approximately passing vertically through the axis of the drum14. The pipe 36 is blanked against one end of the drum vat 38 andextendsoutwardly through a stuffing box 39 at the opposite end, it beingunderstood that the pipe is externally connected with the source ofsupply of the liquid to be frozen which preferably is supplied to thepipe 36 in a precooled condition. The pipe 36 is perforated -throughoutthe length thereof that extends `wit-hin the housing and should belpreferably made vadjustable in a rotary direction so that the incomingliquid may be sprayed against the surface of the drum 14 so that it will`flow in both directions over the drum surface. 'Y

The liquid flowing in the direction of rotation of the druin (Fig. 2)serves to bathe the scraping knife edge, and the frozen mass that isscraped fromthe periphery-of the drum by the lznife. Part of the liquid{iowing in the reverse direction of rotation of the drum will `be frozenbut a sufficient 4amount should be supplied in order to pro- Vide anvexcess to bathe 0E the air bubbles from the portion that is frozen. Anyexcess liquid flowing in 'either direction accumulates inthe bottom ofthe housing. The pipe 37 extends longitudinally of the drum 14, it beingunderstood that the arrangement of the inner end of tclie pipe is thesame as that described in connection with the pipe 36 and that the pipe37 also extends outwardly throu h the end plate through a stuiling boxiot shown). In other words, the arrangement of the pipe 37 and itsmounting is identical with the mounting for the pipe 36, the pipe 37how- Y ever being positioned just below the scraping knife.

lhe liquid from the pipe 37 is discharged against the drum in thedirection of its rotation and the liquid should be applied with sucient'force to cause. a considerable velocity relative to the surface of thedrum, spraying a relatively thin film of liquid against the drumperiphery which readili'y freezes due tothe fact that the wall 14` has avery high heat conductivity and the heat from the liquid is rapidlywithdrawn by the action of the refrigerant in the drum. The excessliquid 'accumulates in the bottom of the housing and where a liquid suchas raw water is used, it is preferable to continuously withdraw thewater from the bottom of the housing to prevent concentration ofimpurities.` The excess liquid is withdrawn through any suitable form ofdischarge pipe (not shown) which ma-y be controlled by an automaticlevel lcontrol 40 and the level of the water may or may not be incontact with the lower periphery of the drum. In any event it should notrise to any considerable extent above the lower segment of the drum.

The accumulated excess of the liquid in the bottom ofthe housing will bemaintained at a temperature closely approximating the freezing point ofthe liquid. The temperature may be regulated by controlling the amountof excess supplied through the supply pipes. Tlie excess accumulation ofliquid in the housing serves to regulate the temperature in addition toits function in eliminating the air bubbles during the freezingoperation. The liquid withdrawn from the housing by suitable means maybe used for reintroduction into the apparatus through the supply pipes.l

The accumulated congealed layer of the liquid that is formed upon theperiphery of the drum is scraped oif and removed there,-

from by a scraping knife 41 set at a tangent,-

to the periphery of the drum and extending outwardly tlierefroniin thedirection of its rotation. The scraping knife extends the full length ofthe drum and is carried by a rod 42 4that extends outwardly through astuffing box 43 in the wall of the housing and is adjustable by a handwheel 44 so as to regulate the contact of the edge of the `knife withthe periphery ofthe drum.

lAs the frozen liquidjf is scraped from the drum by the scraping knife41, it is deiiected into a rectangular mold comprising a bottom wally 45and side walls 46 and 47, said walls extending longitudinally of thehousing within the segment 3 and outwardly for some distance beyond oneend of the housing as clearly illustrated in Fig. 3. 'I lie side wall'46 has an outwardly extending wall substantially in the plane tangentialto the periphery of the drum, the outer edgeof which'is near the outeredge of the knife blade and serves to catchand deflect theseparatedfrozen particles into the mold.

The :mold is formed with. a cover in two sections, the section 48 whichcovers the an open end. The portion of the cover within the housingcomprises a sliding plate 49 that -is arranged to slide outwardly into aclosed -housing 50. vThe entire mold, in-

, reciprocated to open andrlose within the housing of the apparatus.lThe `follower head 51 is operated by a' piston construction including apiston rod 52 that extends througha st'uiing box 53 -in the end wall 'ofthe housing being connected directly to the follower head 51 at itsinner en d. The piston rod extends through a stuliing box 54 in the endof a pistoncylinder 55 mounted extcriorly of the housing. oftheapparatus. A piston'v 56 is mounted in thepiston cylinder and isarrangedto-reciprocate in the piston to 'move the follower head underforce forwardly inthemold cavity and to return the follower .head to theposition .shown in Fig. 3 after it has served to compressvthe frozenparticles accumulated in the mold. f TheI discharge end of the mold isfitted with asimlarfclose-fitting follower head 57 which is' operated-in the same manner and controlled to move in a direction opposite tothe follower head 51 so that by the opposite movement of ythe followerheads '51 and 57, the separated particles or frozen .bod-ies will becompressed, after which the follower head 57 may b e withdrawn from` thedischarge end of the mold and lby moving the follower head 51 forward,-the compacted' frozen body in the formof a cake may be moved out of Ythemold. It is preferable that some degree of heat'should be applied to theexterior'portion of the mold to prethe apparatus.

vent the cake from adhering to the side walls and to facilitate theremoval thereof.

. The movable section 49 of the cover is adapted to be reciprocated bmeans of a rod 58. thatV extends outwar 1y through a stuiing box 5 9 inthe end of'thehousing of This rod 58 extends into a. plston cylinder 60through a stuling box 61, said vrodcarrying at'its end a piston 62Iwhich pis'ton is double-actingfor moving cover section 49 intov 'a4position to cover tlclllals WlthOllt depal'tlllg flOm the- Splllt' thethe nmold and to a position exterior of the housmg of the apparatus touncover the v mold. L

It will be understood that the particles or frozen'bodies scraped fromthe vdrum are accumulated in the interior section 'of the mold when thecover section 49 is withdrawn from the top thereof, The cover sectionis. then moved to cover themold and the follower heads .are operated asabove described the lmold is reset for receiving the accumulation bywithdrawing the cover section 49,'-

that part of the frozenlliquid that h as accumulated upon the upperfaceof the cover section will fall into the mold. The operation of formingthe cakes may berepeated as a continuous operation.

vIt will bel noted that the mold is separated from the housing by abaliie wall 63 but that there is a port 64'in the baffle wall so thata.portion of the mold will be submerged in `the excess liquid in thebottom of the housing, serving to maintain the walls of the lmold-at atemperature under vwhich the separated ,particles or frozen bodies maybe readily compacted and sufoiently high to preventA the adherence ofthe frozen cake to the walls of the mold.

While I have described in some detail the construction vof the -mold asa convenient way of forming cakes of the frozen liquid,

the specific construction of the I nold is not part of the invention andis only one way of removing the frozen bodies from the apparatus, Themold may bev dispensed with' and the frozen bodies scraped from the drummaybe discharged directly into the excess liquid in the bottom of thehousing and re- 'moved therefromby afcontinuous conveyor fitted to thehousing, said. conveyor being of the form and type described anddisclosed in my copending application Serial No.-

Itis contemplated -that the supply of refrigerant may be `convenientlycontrolled automatically by a thermostat device, the

control elementof which may placed* in` the vapor discharge conduit andthatif desired'the liquid supply may be also automatically controlled bysuitable thermostat devices, the control elements of which may besubjected to the influence ofthe internal temperature of the housing ofthe apparatus.

It is contemplated that be supplied with any suitable llquidrefrigerant, it beilg .pref hydrocarbon refrigerant be utilized.

I 'am aware that the construction of the apparatus may be-modied innumerous par It' is alsocontemplavted that. the arrangement- Jofinternal cross connected troughs of the drum `may/be dispensed with andthat the liquid refrigerant mayl bed to the interior of the drum and byvaryin the speed of rotationthereof by centrifuga the apparatus mayerred, however, that a,

irectly supplied f action, the liquid may be kept in contact with thedrum surfaces.

It will be understood that the speed of rotation of the drum may beregulated to control the refrigerating action of the apparatus. l

What I claim and desire to secure by Letters Patent is:

1. In a refrigerating apparatus, the combination of a hermeticallysealed housing, a hollow drum adapted to be rotated in the housing,means for admitting a liquid' refrigerant to the interior of said drum,means for maintaining a relatively small amount of liquid refrigerantagainst a relatively large area of the interior Wall of the drum, meansfor admitting a liquid to be frozen to the exterior of said drum, meansfor removing the frozen liquid from the exterior of the drum, and meansfor compacting and removing the frozen liquid in cake form from saidhousing.

2. In a refrigerating apparatus, the com bination with a housing of arotary drum mounted therein, means for admitting liquid refrigerant tothe interior of said drum, internal troughs supported by the Wall ofsaid drum and adapted to deflect the liquid refrigerant .against theinner periphery of the drum, and mea-ns for admitting liquid to theexterior of said drum.

3. In a refrigerating apparatus, the combination with a housing of arotary drum mounted therein, internal troughs supported by the Wall ofsaid drum, means for admitting liquid refrigerant to the interior. ofsaid drum, ,said liquid being distributed against the inner pcripheryofthe drum by said troughs, and means for admitting liquid to the exteriorof said drum, said troughs being arranged for intereommunication.

4. In a refrigerating apparatus, a sealed heat insulated housing, ahollow drum arranged to rotate Within the housing, an axial supply pipeadapt-ed to admit a liquid r'efrigerant to the interior of said drum, anaxial pipe at the opposite end of said drum adapted to withdraw theexpanded vapors from the drum, a series of internal intercommunicatingtroughs a-rranged to distrlbute the liquid Within the drum against theinner periphery thereof, a liquid supply plpe arranged above the drumand having a series of discharge nozzles for discharging liquid againstsaid drum, and .an adjustable knife adapted to remove the layer of iceformed on the drum.

5. In a 'refrigerating apparatus, an hermetically sealed chamber, arotary drum Within said chamber, means for admitting a refrigerant tothe interior of said drum, a spray device for spraying liquid on theexterior of said drum, a partition in said drum constituting a trap forthe liquidv in the. bottom of the chamber, a scraping device ar? rangedto remove the liquid congealed on said drum, an adjusting deviceoperable exteriorly of the housing for adjusting said scraping device,and means located within the housing for confining and compacting thecongealed liquid scraped from the drum.

6. In a refrigerating apparatus. an hermetically sealed chamber, arotary drum Within said chamber, means for admitting a refrigerant tothe interior of said drum, a spray device for spraying liquid on theexterior ofsaid drum, a partition in said drum constituting a trap forthe liquid in the bottom of the chamber, a scraping device arranged toremove the liquid congealed on said drum, and means located Within thehousing for confining and compacting the congealed liquid scraped fromthe drum.

7. In a refrigerating apparatus, an hermetically sealed chamber, arotary drum Within said chamber, means for adm'itting a refrigerant tothe interior of said drum, a spray device for spraying'liquid on theexterior of said drum, a partition in said drum constituting a trap forthe liquid inthe bottom of t-he chamber, a scraping device arranged toremove the liquid. congealed on said drum, and a mold located Within thehousing near the bottom thereof for receiving and compacting the frozenliquid scraped from the drum. f

8. In a refrigerating apparatus, an hermetically sealed chamber, arotary drum within said chamber, means for admitting a refrigerant tothe interior of said drum, a spray device for spraying liquid on theexterior of said drum, a partition in said drum constituting a trap forthe liquid in the bottom of the chamber, a scraping device arranged toremove the liquid congealed on said drum, a mold located Within thehousing .near the bottom thereof for receiving and compacting the frozenliquid scraped from the drum, and means lfor controlling the liquidlevel in the bottom of said drum.

- SAMUEL C. CARNEY.

